The carbon-supported Pt nanoclusters (20 wt% metal) electrodes have been tested as oxygen reduction catalysts in 0.1M KOH solutions. The novel non-conventional microporous-mesoporous carbide derived carbon powder, synthesized from molybdenum carbide (Mo 2 C) at 750 • C using the high-temperature chlorination method, has been used as an electrocatalyst support for oxygen electroreduction. For comparison, the corresponding parameters for commercially available VulcanXC72 and (20 wt%) Pt-VulcanXC72 have been obtained. Results of the X-ray diffraction analysis show that the Pt nanoclusters have been deposited mainly as the face-centered cubic (fcc) crystals at both carbon supports. The Pt particles were distributed uniformly on the porous carbon supports, and the average particle size of the Pt nanoclusters at (20 wt%) Pt-C(Mo 2 C) and at (20 wt%) Pt-VulcanXC72 were 42 and 57 Å, respectively. The (20 wt%) Pt-C(Mo 2 C) catalyst demonstrated higher activity (calculated effective electrochemical surface area A eff = 0.485 cm 2 ) with high specific surface area S BET = 1600 m 2 g −1 toward the oxygen electroreduction reaction at room temperature compared with that for the (20 wt%) Pt-VulcanXC72 (A eff = 0.320 cm 2 ) with S BET = 180 m 2 g −1 . The four-electron oxygen reduction mechanism has been established for both, i.e., the (20 wt%) Pt-C(Mo 2 C) and (20 wt%) Pt-VulcanXC72 catalysts based electrodes.

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Oxygen reduction reaction in alkaline solutions at various carbons (C(Mo2C), Vulcan), and carbon supports, activated with 20wt% Pt-nanoparticles has been studied in 0.1 M and 1.0 M KOH aqueous solutions. Experimental data show important contribution from the C(Mo2C) carbon support to the reduction kinetics of oxygen. Scanning electron microscopy, X-ray diffraction, electrochemical cyclic voltammetry and rotating disc electrode experiments have been carried out to characterize the structure and electrochemical behavior of materials prepared.

Micro-and mesoporous carbide derived carbons synthesized from molybdenum and tungsten carbide were used as supports for platinum and Pt-Ru alloy catalysts. The scanning electron microscopy, X-ray diffraction, Raman spectroscopy, high resolution transmission electron microscopy and low temperature N 2 adsorption experiments were carried out to characterize the structure of prepared materials. The kinetics of oxygen reduction was studied using cyclic voltammetry and rotating disc electrode in 0.5 M H 2 SO 4 solution. The synthesized materials exhibited high specific surface area. The platinum or Pt-Ru alloy deposited onto the surface of carbon in the form of nanoparticles or agglomerates of nanoparticles. All catalysts showed high activity towards oxygen reduction.

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